Apoplastic Iron Concentration in Maize Roots Grown Under Sulfate Deprivation

The rate of ammonia production by the chemical oxidation of iron, N2(from air or as pure nitrogen) and water is studied as a function of (1) iron particle size, (2) iron concentration, (3) temperature, (4) pressureand (5) concentration of the alkaline reaction medium. The reaction meduium consists of an aqueous solution of equal molal concentrations of NaOH and KOH (Na0.5K0.5OH). We had previously reported on the chemical reaction of iron and nitrogen in alkaline medium to ammonia as an intermediate step in the electrochemical synthesis of ammonia by a nano-sized iron oxide electrocatlyst. Here, the intermediate chemical reaction step is exclusively explored. The ammonia production rate increases with temperature (from 20 to 250°C), pressure (from 1 atm to 15 atm of air or N2), and exhibits a maximum rate at an electrolyte concentration of 8 molal Na0,5K0,5OH in a sealed N2reactor. 1-3 µm particle size Fe drive the highest observed ammonia production reaction rate. The Fe mass normalized rate of ammonia production increases with decreasing added mass of the Fe reactant reaching a maximum observed rate of 2.2x10-4mole of NH3h-1g-1for the reaction of 0.1 g of 1-3 µm Fe in 200°C 8 molal Na0.5K0.5OH at 15 atm. Under these conditions 5.1 wt% of the iron reacts to form NH3via the reaction N2+ 2Fe + 3H2O ®2NH3+ Fe2O3.

Download Full-text

ECOLOGICAL AND PHYSIOLOGICAL ASSESSMENT OF CHEMICAL COMPOSITION OF DRINKING TAP WATER IN KHANTY-MANSIYSK AND SALEKHARD

Ulyanovsk Medico-biological Journal ◽

10.34014/2227-1848-2020-3-159-167 ◽

2020 ◽

pp. 159-167

Author(s):

V.V. Lapenko ◽

L.N. Bikbulatova ◽

E.M. Ternikova

Keyword(s):

Drinking Water ◽

Chemical Composition ◽

Water Samples ◽

Tap Water ◽

Iron Concentration ◽

Absorption Spectrometry ◽

Northern Region ◽

Transport Processes ◽

Magnesium Concentration ◽

Geochemical Environment

Water is very important for humans, as it is a solvent for metabolic products. Moreover, it is necessary for metabolism, biochemical and transport processes. The elemental status in persons depends on the geochemical environment and consumption of bioelements with food and water. The aim of the paper is to conduct a comprehensive assessment of chemical composition of drinking tap water in Khanty-Mansiysk and Salekhard. Materials and Methods. The chemical composition of 100 samples of drinking tap water was analyzed by atomic absorption spectrometry, spectrophotometry and capillary electrophoresis. All in all, there were 50 samples from Khanty-Mansiysk and 50 samples from Salekhard. The results were compared with Sanitary Rules and Norms 2.1.4.1074-01. Results. Drinking tap water in Salekhard contains a significantly higher concentration of iron, which is much above the maximum allowable concentration, if compared to water samples in Khanty-Mansiysk (p=0.03). In the cities under consideration, the water undergoes high-quality reagent-free treatment. However, the deterioration of the water supply networks in Salekhard is 3 times as high as in Khanty-Mansiysk. Calcium and magnesium concentration in water samples from Khanty-Mansiysk is 5.6 and 3.9 times lower than the MAC; in water samples from Salekhard calcium concentration is 6.3 (p=0.008) and magnesium concentration 4.6 (p<0.001) times lower than the MAC. Conclusion. The consumption of ultra-fresh drinking water leads to low intake of bioelements, which are a part of enzymes contributing to the human antioxidant defense and can result in manifestation of cardiovascular diseases. This is especially true for Salekhard with very soft drinking water and high iron concentration, which excess can exhibit prooxidant properties. Keywords: tap water, bioelements, northern region, antioxidants. Вода является важнейшим соединением для человека: необходима в качестве растворителя продуктов метаболизма и протекания обменных, биохимических и транспортных процессов. Элементный статус организма человека зависит от геохимического окружения и поступления биоэлементов с пищей и водой. Цель. Провести комплексную оценку химического состава водопроводной воды городов Ханты-Мансийск и Салехард. Материалы и методы. Методами атомно-абсорбционной спектрометрии, спектрофотометрии и капиллярного электрофореза проанализирован химический состав 100 проб водопроводной воды: по 50 из Ханты-Мансийска и Салехарда. Результаты сравнивали с СанПиН 2.1.4.1074-01. Результаты. В водопроводной воде Салехарда установлена превышающая ПДК и достоверно более высокая концентрация железа сравнительно с водой Ханты-Мансийска (р=0,03). При условии качественной безреагентной водоподготовки в изучаемых городах это обусловлено изношенностью водопроводных сетей в Салехарде, более чем в 3 раза превышающей этот показатель в Ханты-Мансийске. Концентрация кальция и магния в воде Ханты-Мансийска в 5,6 и 3,9 раза ниже ПДК; в воде Салехарда – в 6,3 (р=0,008) и 4,6 (р<0,001) раза ниже ПДК соответственно. Заключение. Употребление ультрапресной питьевой воды на фоне очень малого поступления с водой биоэлементов, входящих в состав ферментов антиоксидантной защиты организма человека, может привести к манифестации кардиоваскулярных заболеваний. Это особенно актуально для г. Салехарда с очень мягкой питьевой водой с повышенным содержанием железа, избыток которого может проявлять прооксидантные свойства. Ключевые слова: водопроводная вода, биоэлементы, северный регион, антиоксиданты.

Download Full-text

In vivo Experiments of Natural Products Protection of Antagonistic Effects of Lead on Iron

Revista de Chimie ◽

10.37358/rc.17.12.5969 ◽

2018 ◽

Vol 68 (12) ◽

pp. 2747-2751

Author(s):

Marioara Nicula ◽

Nicolae Pacala ◽

Lavinia Stef ◽

Ioan Pet ◽

Dorel Dronca ◽

...

Keyword(s):

Aquatic Environment ◽

Iron Homeostasis ◽

Iron Concentration ◽

Antagonistic Effect ◽

Tissue Samples ◽

Antagonistic Effects ◽

In Vivo Experiments ◽

Living Organisms ◽

Toxic Potential

Living organisms take nutrients from the environment, and together with them, substances with toxic potential � such as heavy metals. Lead is one common metal pollutant especially in aquatic environment, from where the fish can be intoxicated very easily. Bioavailability, distribution, toxic action, synergistic and antagonistic effects are characteristics which can alter the fish health. Our experimental study followed the effects of lead overload in water on iron distribution, in different tissues sample Carassius gibelio Bloch fish. We performed the experiment in four different fish groups: control C; lead � Pb (administration of lead in water 0.075mg/mL of water, as Pb(NO3)2 x � H2O); lead (the same dose) and 2% of freeze-dry garlic incorporated into fishes� food � Pb+garlic; lead (the same dose) and 2% chlorella incorporated into fishes� food � Pb+chlorella, for 21 consecutive days. The iron concentration was analysed with AAS (Atomic Absorption Spectroscopy) from gills, muscle, skin (and scales), intestine, liver, heart, brain, ovary, testicles, and kidney. The obtained data presented a significantly decrease of iron content in all tested tissue samples that demonstrated, alteration of iron homeostasis, explained by a strong antagonistic effect of lead on iron. Our experiment showed that biologic active principles from garlic and chlorella act like natural protectors, and potentiate the iron deficiency even in the case of lead overload in aquatic environment, for fish.

Download Full-text

THE IMPACT OF WIND CONDITIONS ON THE LEVELS OF TOTAL IRON CONTENT IN THE SEA OF AZOV

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b4315d1d7c6 ◽

2017 ◽

Author(s):

Yuri Fedorov ◽

Irina Dotsenko ◽

Leonid Dmitrik ◽

...

Keyword(s):

Bottom Sediments ◽

Iron Content ◽

Iron Concentration ◽

Total Iron ◽

Sea Of Azov ◽

Open Area ◽

The Sea Of Azov ◽

Dissolved Iron ◽

The Impact ◽

Taganrog Bay

The distribution and behavior of certain of trace elements in sea water is greatly affected by both physical, chemical and hydrometeorological conditions that are showed in the scientific works of prof. Yu.A. Fedorov with coauthors (1999-2015). Due to the shallow waters last factor is one of the dominant, during the different wind situation changes significantly the dynamics of water masses and interaction in the system “water – suspended matter – bottom sediments”.Therefore, the study of the behavior of the total iron in the water of the sea at different wind situation is relevant. The content of dissolved iron forms migration in The Sea of Azov water (open area) varies from 0.017 to 0.21 mg /dm3 (mean 0.053 mg /dm3) and in Taganrog Bay from 0.035 to 0.58 mg /dm3 (mean 0.11 mg /dm3) and it is not depending on weather conditions.The reduction in the overall iron concentration in the direction of the Taganrog Bay → The Sea of Azov (open area) is observed on average more than twice. The dissolved iron content exceeding TLV levels and their frequency of occurrence in the estuary, respectively, were higher compared with The Sea of Azov (open area).There is an increase in the overall iron concentration in the water of the Azov Sea on average 1.5 times during the storm conditions, due to the destruction of the structure of the upper layer and resuspension of bottom sediments, intensifying the transition of iron compounds in the solution.

Download Full-text

Assessment of Ploy Dopamine Coated Fe3O4 Nanoparticles for Melanoma (B16-F10 and A-375) Cells Detection

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200513084616 ◽

2020 ◽

Vol 20 (16) ◽

pp. 1918-1926

Author(s):

Fahimeh H. Beigi ◽

Soheil Fatahian ◽

Sogand Shahbazi-Gahrouei ◽

Daryoush Shahbazi-Gahrouei ◽

Amin Farzadniya

Keyword(s):

Mr Imaging ◽

Mtt Assay ◽

Fe3o4 Nanoparticles ◽

Normal Skin ◽

Iron Concentration ◽

Positive Effects ◽

Skin Cells ◽

Melanoma B16 ◽

Co Precipitation

Objective: Polydopamine coated iron oxide nanoparticles (Fe3O4@PDA NPs) were synthesized, characterized, and their MR imaging contrast agents and photothermal potency were evaluated on melanoma (B16-F10 and A-375) cells and normal skin cells. To this end, MTT assay, Fe concentration, and MR imaging of both coated and uncoated NPs were assessed in C57BL/6 mice. Methods: Fe3O4 nanoparticles were synthesized using co-precipitation, and coated with polydopamine. The cytotoxicity of Fe3O4 and Fe3O4@PDA NPs on melanoma cells, with different concentrations, were obtained using MTT assay. MR images and Fe concentrations of nanoprobe and nanoparticles were evaluated under in vivo conditions. Results: Findings indicated that uncoated Fe3O4 showed the highest toxicity in animal (B16-F10) cells at 450μg/ml after 72h, while the highest toxicity in human (A-375) cells were observed at 350μg/ml. These nanoparticles did not reveal any cytotoxicity to normal skin cells, despite having some toxicity features in A-375 cells. MR image signals in the tumor were low compared with other tissues. The iron concentration in the tumor was higher than that of other organs. Conclusion: It is concluded that the cytotoxicity of Fe3O4@PDA was found to be significantly lower than uncoated nanoparticles (p <0.001), which allows some positive effects on reducing toxicity. The prepared nanoprobe may be used as a contrast agent in MR imaging.

Download Full-text

Assay of Arabinofuranosidase Activity in Maize Roots

BIO-PROTOCOL ◽

10.21769/bioprotoc.1764 ◽

2016 ◽

Vol 6 (6) ◽

Cited By ~ 1

Author(s):

Liudmila Kozlova ◽

Polina Mikshina ◽

Tatyana Gorshkova

Keyword(s):

Maize Roots

Download Full-text

Influence of Alumina Precursor Properties on Cu-Fe Alumina Supported Catalysts for Total Toluene Oxidation as a Model Volatile Organic Air Pollutant

Catalysts ◽

10.3390/catal11020252 ◽

2021 ◽

Vol 11 (2) ◽

pp. 252

Author(s):

Tadej Žumbar ◽

Alenka Ristić ◽

Goran Dražić ◽

Hristina Lazarova ◽

Janez Volavšek ◽

...

Keyword(s):

Surface Characterization ◽

Iron Concentration ◽

Catalytic Performance ◽

Air Pollutant ◽

Molar Ratio ◽

Homogeneous Distribution ◽

Total Oxidation ◽

Alumina Support ◽

Determining Factors ◽

Volatile Organic

The structure–property relationship of catalytic supports for the deposition of redox-active transition metals is of great importance for improving the catalytic efficiency and reusability of the catalysts. In this work, the role of alumina support precursors of Cu-Fe/Al2O3 catalysts used for the total oxidation of toluene as a model volatile organic air pollutant is elucidated. Surface characterization of the catalysts revealed that the surface area, pore volume and acid site concentration of the alumina supports are important but not the determining factors for the catalytic activity of the studied catalysts for this type of reaction. The determining factors are the structural order of the support precursor, the homogeneous distribution of the catalytic sites and reducibility, which were elucidated by XRD, NMR, TEM and temperature programed reduction (TPR). Cu–Fe/Al2O3 prepared from bayerite and pseudoboehmite as highly ordered precursors showed better catalytic performance compared to Cu-Fe/Al2O3 derived from the amorphous alumina precursor and dawsonite. Homogeneous distribution of FexOy and CuOx with defined Cu/Fe molar ratio on the Al2O3 support is required for the efficient catalytic performance of the material. The study showed a beneficial effect of low iron concentration introduced into the alumina precursor during the alumina support synthesis procedure, which resulted in a homogeneous metal oxide distribution on the support.

Download Full-text